Illuminated screw driver



y 1955 TADAYUKI NAGAMORI 3,185,832

ILLUMINATED SCREW DRIVER Filed Dec. 20, 1961 I I I III/II III/II 1 ,L

. INVENTOR TADAY U K I NAGA MORI BY fidwa,

ATT

United States Patent 3,135,332 ILLUMINATED SCREW DRIVER Tadayuki Nagamori, 851 Yukigaya-cho, Uta-kn, Tokyo, Japan Filed Dec. 20, 1961, Ser. No. 160,853 1 Claim. (Cl. 240-646) This invent-ion relates to an illuminated screw driver, and more particularly to a screw driver in which light rays from an electric bulb within the handle are projected in such a manner as to silhouette the blade end of the screw driver within a circular pattern of light.

An object of the present invention is to provide a screw driver with means in the handle for illuminating the blade of the screw driver so that it may be accurately positioned within a light field. A still further object is to provide a handle of transparent or translucent material containing illuminating means, while at the same time providing wing reflector and condenser lens structures for directing light rays upon the blade of the screw drive-r in a manner in which the blade is projected within the light pattern as a shadow for accurately positioning the blade within the groove of a screw, etc. Other specific objects and advantages will appear as the specification proceeds.

The invention is shown, in an illustrative embodiment, :by the accompanying drawing, in which FIG. 1 is a broken longitudinal sectional view of an illuminated screw driver embodying my invention; FIG. 2, a side view in elevation, partly in section, of the battery and light bulb element; FIG. 3, a front view in elevation of the handle showing the retainer and reflector mem bers of the handle; and FIG. 4, a perspective view showing the forward portion of the handle and the screw driver shank about to be received therein.

In the illustration given, designates a handle formed of resin plastic which is transparent or translucent. For example, polymerized methyl methacrylate (Lucite), polyethylene, or any other transparent or translucent resin may be employed. The handle is formed with a hollow interior 11 adapted to receive a flashlight battery 12 engaging the contact of a socket member 13 carrying an electric light bulb 14 partly enclosed by a cylindrical reflector 15. A spring 16 is urged against the battery 12 by a threaded closure 17 and the spring engages a conductor 18 which extends forwardly above the metal reflector 15. A slidable button 19 is adapted to engage the cam surface of the front end portion 20 of the conductor 13 so as to bring it into engagement with the metal reflector when the bulb is to be illuminated, the current flowing from the battery 12 through the socket contact, light bulb, and thence through the conductor 18, spring 16, and back to the battery 12. Since such structure is well known, a further detailed description is believed unnecessary.

The forward end of the transparent plastic handle is curved to form a convex lens portion 21 which cooperates with the reflector-retaining means in forming a novel light pattern which will be described more fully hereinafter.

Within the front portion 21 of the handle 10, there is formed a longitudinal slot 22 having laterally-extending openings 23 for receiving a spring-retainer member 24. The spring-retainer member 2 as shown best in FIG. 3, has metal reflector wings 25 which receive light rays from the light bulb and direct them forwardly through the convex lens 21, with the result that the light rays are directed forwardly in intensified form to silhouette the front enlarged blade portion 26 of the screw driver shank 27. The shank 27 has at its rear laterally-projecting flanges 28 which are received within the wings 25 of the spring member 24.

Patented May 25, 19%?) In the use of a tool forwardly of a light-projecting source, the tool itself forms a serious obstruction, tending to diffuse the light rays and to form a dark center, making it diflicult to align the tool with an object even though there is a pattern of light around the tool. In the use of the screw driver, means connecting it to the handle must be employed for preventing rotation of the screw driver shank, and such means tend to obscure the central portion of the light pattern so that the operator of the tool cannot accuratey place the blade or point of the tool in the desired opening. I have discovered that by using a retainer which has reflector wing surfaces, the light rays from the bulb will pass forwardly through the transparent resin material, striking the reflectors and being directed upwardly through the cone or convex surface 21, and the rays are condensed or straightened so as to make the blade of the screw driver become silhouetted in the light pattern. Instead of the blade being obscured Within a dark area, the blade is caused to stand out prominently in relief within the light field so that it can be readily and accurately positioned. In the foregoing operation, the retainer wings 25 serve not only to lock the shank of the screw driver tool against rotation, but project the light rays in a plane aligned with the light bulb so that the condensed rays outline the blade of the screw driver as above described.

While in the foregoing specification, I have set forth a specific structure in considerable detail for the purpose of illustrating my invention, it will be understood that such details of structure may be varied widely by those skilled in the art without departing fir-om the spirit of my invention.

I claim:

An illuminated screw driver, comprising a hollow tubular insulating handle formed of translucent resin plastic,

a flashlight bulb and battery housed within saidhandle, a cylindrical reflector about said bulb, means in said handle including a manually-operated switch for 1 coupling said bulb and battery for illuminating said 'bulb,

said handle having a convex forward face forming a condenser lens and a slot extending axially therefrom with laterally-extending openings,

a metal spring retainer mounted within said slot and having pairs of laterally-extending wings received in said lateral openings, and

a screw driver member having a shank provided with laterally-extending flanges held within said retainer, with each flange being confined by a pair of said wings,

said wings having reflective surfaces extending axially of said handle between said condenser lens and bulb, whereby said wings are adapted to reflect rays of light from said bulb into a condensed pattern about said screw driver member.

References Cited by the Examiner UNITED STATES PATENTS 1,951,097 3/34 Lyeso 240-646 1,9965 63 4/35 Billings 240 6.46 2,311,439 2/43 Iwanowicz 2406.46 2,408,601 10/46 Blauvelt 240-6.46 2,527,492 10/50 Cleary et al.

2,706,769 4/55 Cools 240-6.46

NORTON ANSHER, Primary Examiner, LAWRENCE CHARLES, Examiner. 

